This invention relates generally to a device and method for anchoring tissue within a body and, more particularly, to a suture anchor for use in surgical procedures requiring attachment of tissue, such as ligaments, tendons and the like, to other, preferably harder or more fibrous, tissue, such as a bone surface.
Suture anchors are used in surgical procedures wherein it is necessary for a surgeon to attach tissue to the surface of bone, for example, during joint reconstruction and ligament repair or replacement. Suture anchors generally comprise an anchor portion for fixed attachment to the bone, and a suture portion extending from the anchor portion used to connect the tissue to the bone. The anchor portion is often a generally cylindrical body having a sharp pointed end. An impact tool is typically used for driving the pointed end of the anchor into the bone. The outer surface of the anchor portion may be barbed or serrated to prevent the suture anchor from being withdrawn from the bone. The outer surface of the anchor portion could also be threaded and a driver, turned by a conventional drill, used to seat the threaded anchor portion into the bone. The anchor portion may also be fitted into a hole formed in the bone.
With the anchor portion securely in the bone, the suture portion is used for securing the tissue to the bone. The procedure typically involves passing a needle with the suture attached through the tissue. The tissue is advanced along the suture and tension is applied to the suture to draw the tissue tightly against the bone. The needle is removed and the tissue is secured against the bone by knotting the ends of the suture extending from the tissue. The knot is brought down to the surface of the tissue and tightened sufficiently to secure the tissue and bone in close approximation to promote reattachment and healing. A sliding retainer is sometimes used with the suture to pin the tissue against the bone.
There are other conventional suture anchors for attaching tissue to bone. For example, the anchor portion could take other forms including a staple which is driven into the bone surface with the suture positioned between the staple legs and the staple web fixing the suture to the bone surface. Also, a pair of closely-spaced holes can be drilled in the bone for passing the suture into one hole and out the other. However, these procedures are often difficult to perform, particularly in areas with limited access, such as deep wounds.
Further, conventional methods for approximating tissue to bone using a suture are difficult and inefficient because the procedure requires manipulation of the suture for securing the tissue in place. This is a time-consuming part of most surgical procedures, particularly in microsurgery and endoscopic surgery where there is insufficient space to properly manipulate the suture.
For the foregoing reasons, there is a need for an improved suture anchor for use in surgical procedures. The new suture anchor should eliminate the need for tying the suture to hold the tissue against the bone or other tissue surface. The method for using the suture anchor in surgical applications should allow a surgeon to approximate tissue to the bone or tissue surface in an efficient manner. A particularly useful new suture anchor would be used in surgical applications where space is limited such as microsurgery, endoscopic surgery or arthroscopic surgery.
According to the present invention, a suture anchor is provided for approximating tissue to bone or other tissue. The suture comprises an anchor member adapted to fixedly engage the bone for securing the anchor member relative to the bone. A plurality of sutures are mounted to the proximal end of the anchor member so that the sutures extend outwardly from the anchor member. Each suture has a sharp pointed distal end for penetrating the tissue and a plurality of barbs extending from the periphery of the body. The barbs permit movement of the sutures through the tissue in a direction of movement of the pointed end and prevent movement of the sutures relative to the tissue in a direction opposite the direction of movement of the pointed end.
Also according to the present invention, a method is provided for approximating tissue to a bone or other tissue to allow reapproximation and healing of the tissue and bone in vivo. The method uses a suture anchor including an anchor member adapted to be fixedly mounted to the bone and a plurality of sutures extending from the anchor member. The method comprises the steps of providing on each suture a sharp pointed distal end for penetrating the tissue and a plurality of barbs extending from the periphery of the body. The barbs permit movement of the sutures through the tissue in a direction of movement of the pointed end and prevent movement of the sutures relative to the tissue in a direction opposite the direction of movement of the pointed end. The anchor member is secured in the bone such that the sutures extend from the bone surface and a pointed end of a first suture is inserted into the tissue. The end of the first suture is pushed through the tissue along a curvilinear path in a direction away from the bone until the point at the end of the first suture extends out of the tissue at an exit point in the periphery of the tissue longitudinally spaced from the point of insertion. The pointed end of the first suture is gripped and pulled out of the tissue for drawing the first suture through the tissue while approximating the tissue adjacent the bone along the suture and leaving a length of the first suture in the tissue. The pointed end of the first suture is then inserted into the periphery of the tissue adjacent the exit point and pushed through the tissue along a curvilinear path in the direction away from the bone until the pointed end of the first suture extends out of the tissue at an exit point in the periphery of the tissue longitudinally spaced from the previous insertion point. The pointed end of the first suture is gripped and pulled out of the tissue for drawing the first suture through the tissue leaving a length of the first portion of the suture in the tissue. These steps are repeated with the first suture for advancing longitudinally along the tissue in the direction away from the bone. A second suture is then introduced into the tissue and the previous steps repeated so that the exit and entry points of the second suture are adjacent the corresponding exit and entry points of the first suture and the path of the second suture substantially mirrors the path of the first suture.